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Multi-Parameter Observation of Pre-Earthquake Signals in Atmosphere-Ionosphere. Case Study for M7.1 M7.1 Ridgecrest, CA Earthquake of July 2019

Session: Application of Remote Sensing and Space-Based Earth Observations Data in Earthquake Research I

Type: Oral

Date: 4/21/2021

Presentation Time: 06:00 PM Pacific

Description: 

We present a multi-parameter analysis of transient phenomena observed in the Earth's atmosphere-ionosphere environment plausibly associated with M6.4 of Jul 4, 2019, and M7.1 of Jul 6, 2019, Ridgecrest California. We collect operational data from two satellites, ground data, and one assimilation model probing atmosphere/ ionosphere, such as 1. Outgoing long-wavelength radiation (OLR obtained from NPOESS) on the top of the atmosphere (TOA); 2. Electron Density (Te) from the ionospheric plasma data (Langmuir Probe, LAP) from China Seismo-Electromagnetic Satellite (CSES, also called ZhangHeng-1).3. Very Low Frequency (VLF) modulated signals from several VLF/LF transmitters; 4. Weather Data -Temperature, Atm. Pressure and Relative humidity; 5.Atmospheric chemical potential (ACP) obtained from weather models and 6. The electron density variations in the ionosphere via GPS Total Electron Content (GPS/TEC). NOAA satellite thermal observations on Jun 24 show an increase of OLR near the future epicenter. The VLF signal received at Orange, CA, was strongly disturbed on all tracks on Jun 22, and the signal perturbations were also observed on Jun 25 and on Jul 6. The increases in ACP on June 30/Jul 1 was measured near the epicentral area and coincided with the anomaly of Te from LAP of CSES1 satellite. The GPS/TEC data indicated an increase of electron concentration in the ionosphere on Jun 30 and Jul 1. We compare the precursory phenomena in the ionosphere and atmosphere of 2019 Ridgecrest compared to Hector Mine 1999 in the same areas. We analyzed two strong earthquakes of the same magnitude M7.1 in the same region with a time span of 20 years. We provide comprehensive analysis, determine the precursory period for both earthquakes, and demonstrate the self-similarity and uniqueness of atmospheric and ionospheric precursors. We show that only by integrating data from multiple sensors in space and on the ground we could observe the pre-earthquake evolution patterns in the atmosphere-ionosphere environment.

Presenting Author: Dimitar Ouzounov

Student Presenter: No

Authors